Title :
Study of electronic state of supported gold nanospecies by IR spectroscopy
Author :
Martynyuk, O. ; Pestryakov, A. ; Bogdanchikova, N. ; Tiznado, H. ; Zepeda, T.A. ; Tuzovskaya, I.
Author_Institution :
Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 14, C. P. 22800, Ensenada, México
Abstract :
The nature of different Au species supported on hexagonal mesoporous silica has been studied by infrared spectroscopy of adsorbed CO. Experiments revealed existence of the following states of supported gold: neutral metal particles Au°, ions Au+ and a number of partly charged states Auδ+ with different effective charge. Redox pretreatments (vacuum, O2 and H2) of Au/SiO2 at the different temperatures (100, 300 and 500°C) exert a significant effect on the electronic state of supported Au species. The experiments showed high stability of Auδ+ states under all treatments; that may prove their active role in catalytic properties of gold.
Keywords :
adsorption; carbon compounds; catalysis; gold; infrared spectra; mesoporous materials; nanofabrication; nanoparticles; nanoporous materials; oxidation; porosity; reduction (chemical); silicon compounds; surface states; Au-SiO2; CO; adsorbed carbon oxide; catalytic properties; effective charge; electronic state; hexagonal mesoporous silica; infrared spectroscopy; neutral metal particles; partly charged states; redox pretreatments; supported gold nanospecies; temperature 100 degC; temperature 300 degC; temperature 500 degC; Gold; Ions; Mesoporous materials; Oxidation; Silicon compounds; Spectroscopy; CO adsorbtion; gold catalyst; mesoporous silica; redox pretreatments;
Conference_Titel :
Strategic Technology (IFOST), 2012 7th International Forum on
Conference_Location :
Tomsk
Print_ISBN :
978-1-4673-1772-6
DOI :
10.1109/IFOST.2012.6357581
